[Feature Request]: Support multiple pairs of NPUs for point-to-point transfer in transfer_engine_ascend_direct_perf.cpp

### Describe your feature request

Hello,
I am currently using the example **transfer_engine_ascend_direct_perf.cpp** in the mooncake-transfer-engine project.
I noticed that this example currently **only supports single-pair NPU point-to-point data transfer** (one source NPU to one destination NPU).
I would like to ask:
Does the current transfer engine framework support **multiple pairs of NPUs transmitting point-to-point data** at the same time?
Is there a plan to support multi-pair NPU direct P2P transfer in this example?
If it is already supported, could you please provide a brief guide or sample code about how to implement it?
Thank you very much for your excellent work!

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